Question

A car travels 100 Km at a uniform speed of 40 Km/h and the next 125Km at a uniform speed of 50 Km/h.Find the average speed of the car?

Answer 1

let da time taken to travel 100 km is t₁
t₁=100/40
time taken to travel 125 km = t₂
∴t₂= = 125/50
we know,
average speed = total distance / total time
                        = 100+125/100/40+125/50
                         = 225/ 5
                         =45km/hr

Answer 2

Answer:

45 km/hr

Step-by-step explanation:

Case 1 :

Distance = 100 km

Speed = 40 km/hr

$Time = \frac{Distance}{Speed}$

$Time = \frac{100}{40}$

Case 2:

Distance = 125 km

Speed = 50 km/hr

$Time = \frac{Distance}{Speed}$

$Time = \frac{125}{50}$

Average speed = $\frac{\text{Total distance}}{\text{total time}}$

Average speed = $\frac{100+125}{\frac{100}{40}+\frac{125}{50}}$

Average speed = $45$

Hence The average speed of car is 45 km/hr